Vertical finder for aircraft



Feb. 16 ,1926. 1,573,269

C. L. PAULUS El' AL VERTICAL FINDER FOR AIRCRAFT Filed July 17, 1924 Patented Feb. 16, 1926.

UNITED STATES y "1,573,269 PATENT OFFICE.

CHARLES L. PAULUS, ROBERT KA-UCH, AND HENRY INGLIS, F DAYTON, OHIO.

VERTICAL FINDER FOB AIRCRAFT. ,f

Application n led July 17, 1924. Serial No. 726,525.

To all lwhom' z't may concern." Y

Be it known that we, CHARLES L. PAULUs, ROBERT KAUCH, and HENRY B. INGLIs, citizens of the'United States, residing at Dayton, in the county of Montgomery and vState, of Ohio, have invented certain new and useful Improvements in Vertical Finders for Aircraft, of which the following is a speciiication.

to be used on aircraft on bomb sights and other instruments and in calibrating and purpose gyroscopes, pendulums, or the like.

More specifically, the invention provides an instrument using the horizon as apoint of reference which comprises a revolving relector for sighting the horizon from' Vwhich it is possible'to determine the point of zero inclination b noting when the image of the horizon in t e reflector approaches a fixed and approximately straight line, means being' provided on the instrument for mounting an instrument to be calibrated, tested, or

corrected, as the case may be.

The invention is illustrated'in the accompanying drawing, in which:

Fig. 1 is a diagram showing the principle upon which the mstrument operates.'

and partly in secti'oli of y duce when. there is a slight inclination, and

Fig. 2 is a front view Eartly in elevation tain portions bein broken away.

, Fig. B is a side e evation of the upper portion of the instrument.

Fi 4-is a diagram showing an image prothe exact vertical is almost found, and

Fig. 5 is a similar view showin an image produced (when the tube is exact y vertical.

Throughout the views the same .reference numerals are applied to the same parts.

Referring to Fig. 1, the instrument comprises a fixed reflector or prism 10 'sighted horizontall with the eye. The image seen on Ythe re ector is reflected from a revolving reiiector or prism 12 along a vertical line 13. The reector 12 is adjusted to'secure an image of` the horizon along','the lines 14 and 15. The adjustment of the reiector 12 is made to secure an ima on the reflector 10 :at about the middle of t e circle 16, as shown L in'fFigsA and 5. In case the instrument is notiuite vertical, but closely approachesthis 'poi-nt jof-zerefinclinationfthe image ofthe i e instrument, cer-- reflector 12 is revolved, and will ap earfto the eye at 111 as a blurred or wavy 'ne 17. 'lhe instrument is adjusted until the image in the reflector 10 appears as a fixed and approximately straight line 18 as shownin Fig. 5. At this point the readin of the instrument to be calibrated, teste or corrected,

is noted and in the case of an instrument al- This invention relates to a vertical finderl may be turnedslight to suit the convenience 'of the observer w has the eye piece 24 to his eye. A tubel to which the eye plece 24 is clamped, communicates with a case 26 in which the fixed reflector or prism 10 is mounted. The latter has its reflecting surface inclined at an angle of approximately to theA horizontal so that si hting is along a horizontal line and the re action of the image is along a vertical line at right portion 21 intermediate its ends, to vbeA horizon in 'the reflector 10 will move Aas the j an les. It is when the vertical line at 13 is v tru y vertical that an image such as that shown in Fig. 5 is secured in the reflector 10.

10 but is adjustable on trunnions 30 to securev the proper divergence of the yline of sight 15 to secure an image of the hor1zon, v arying under diierent atmospheric condltions, or Vat different elevations.

A lrnurled knob 31 is fixed on one of theM trunnions 30 outside the head 28for adjusting the prism. A calibrated dial 32 movable relative-to an index on the head 28 may be provided soi that a setting of the prism once made may be reproduced. v A sh` ort guard tube 33 is provlded communlcatmg with the head 28 through which-,the horl- .zon is sighted.

The prism 12 is revolved preferably a small electric motor 34 held by clamps 35 upon the'tube 20. Apinion 36 on the armature shaft of the motor 34 meshes with a gear 37 secured to the head 28 by screws 38. The gear` 37 has a recess 39 to receive the :flange 29 of the tube 20 to provide a swivel bearing for the head 28. It will be noted that the tube extends oppositely from the motor .34 at the lower end of the tube 20 and offsets its weight sufficiently to maintain proper balance so that the tube does not tend of itself to any inclination.

We claim 1. In a vertical nder for aircraft, a laterally viewing reflector, means for mounting said refiector to rotate about a substantially vertical axis; revolving means for said reflector for constantly revolving the same at a ra id speed to secure a continuous image o the horizon, and a stationary sighting 7means vertically arranged relative to said reflector for viewing the image of the horizon on the reflector.

y 2. In av vertical finder for aircraft, a

laterally viewing refiector, means for mounting said reflector 'to rotate about a vertical axis, revolving means for said reflector for constantly revolving the same at a rapid speed to secure a continuous 'image of the $0 horizon, and a. second reflector stationary and vertically arranged relative to said first reflector to reflect the image. v

3. In a vertical finder, a support, a vertical tube adjustable in said support, a head revoluble on one end of said tube,a reflector viewing laterally mounted in 'said head, driving means for said reflector for continuously revolving the reflector ata rapid speed to secure a continuous image of the horizon, a casing fixed on the free end of said tube having a lateral sight opening, and a second reliector in said casing.

4. In a vertical finder,` a support, a vertical tube universally adjustable in said support, a head revoluble on one end of said tube, a reflector viewing laterally mounted in said head, a motor mounted on said tube, earin between said motor and said head for driving the latter, a. casing on the opposite end of5 said tube, and a second reflector in said casing. 5. In a vertical finder for aircraft as set forth in claim 1, means fof adjusting said reflector about -a substantially horizontal axis.

In testimony whereof we aix our signatures.

CHARLES L. PULS.

ROBERT KAUCH.

HENRY B. INGLIS. 

